Conventionally, liquid discharge devices are used, which discharge liquid to a medium and form a discharged liquid material. Liquid may be discharged to various-shaped media by using such a liquid discharge device. For example, liquid may be discharged to a curved surface of a medium. PTL 1 discloses a liquid discharge device which is provided with a discharge unit that discharges liquid along a predetermined curvature and which can discharge liquid to a medium having the predetermined curvature.
Further, a liquid discharge device that discharges liquid by relatively rotating a medium and a liquid discharge unit is also used. However, for example, when liquid is discharged to a circumferential portion of a medium having a conic shape or a truncated conic shape by using such liquid discharge devices, a distance between adjacent droplets varies because a relative moving distance of the medium per unit time varies when the liquid is discharged, so that the quality of the discharged liquid material may degrade. In other words, the relative moving distance of the medium per unit time is large in a portion having a large diameter and the relative moving distance of the medium per unit time is small in a portion having a small diameter. Therefore, the distance between adjacent droplets is large in a portion having a large diameter and the distance between adjacent droplets is small in a portion having a small diameter, so that the quality of the discharged liquid material may degrade. Thus, for example, PTL 2 discloses a liquid discharge device which can adjust a diameter of discharged ink droplet according to the relative moving distance of the medium per unit time when the liquid is discharged.